Periodic Reporting for period 2 - iPLUG (Distributed multiport converters for integration of renewables, storage systems and loads while enhancing performance and resiliency of modern distributed networks)
Reporting period: 2024-03-01 to 2025-08-31
IPLUG general objective is to design a new breed of multiport converters and develop the methodologies to locate, size, operate and control multiple converters in distribution networks with high penetration of renewables and various AC and DC loads.
* Objective 1: Requirements, architecture and assessment of multi-port converters including high penetration of renewables, energy storage and different AC and DC loads.
* Objective 2: Design the hardware and control of multiport converters for medium-voltage applications.
* Objective 3: Design the hardware and control of multiport converters for low-voltage applications.
* Objective 4: Optimization based methodology for location and sizing of distributed multiport converters.
* Objective 5: Application of advanced operation and control techniques for local and coordinated control of multiport converters in a distribution network for optimised, stable and secure operation.
* Objective 6: Helping rapid penetration and acceptance of renewable energy and electrical systems by enhancing the environmental, social and economic aspects.
* Objective 1: Requirements, architecture and assessment of multi-port converters including high penetration of renewables, energy storage and different AC and DC loads.
* Objective 2: Design the hardware and control of multiport converters for medium-voltage applications.
* Objective 3: Design the hardware and control of multiport converters for low-voltage applications.
* Objective 4: Optimization based methodology for location and sizing of distributed multiport converters.
* Objective 5: Application of advanced operation and control techniques for local and coordinated control of multiport converters in a distribution network for optimised, stable and secure operation.
* Objective 6: Helping rapid penetration and acceptance of renewable energy and electrical systems by enhancing the environmental, social and economic aspects.
Objective 1:
Reviewed grid codes and standards for multiport power converters (MPCs) at low and medium voltages, identifying where MPCs deliver value in distribution networks using quantitative KPI metrics. Assessed the strengths and weaknesses of existing MPC topologies, aligned with relevant KPIs. Facilitated partner discussions on the design of low and medium voltage MPCs, using insights from code and topology reviews to define essential port requirements. Developed case studies and compiled data while also reviewing control and communication technologies applicable to MPCs.
Objective 2:
Developed simulation models for isolated, non-isolated, and hybrid multiport converters with two AC ports and one DC port. Designed and experimentally validated modulation and control strategies for various operation scenarios. Explored active bridge DC–DC converters for isolation stages and compared outer-loop control strategies in modular multilevel converters. Implemented grid-forming controls for improved resilience in weak and islanded networks, and compared topologies for soft open point applications. Developed and validated zero-voltage switching optimization and voltage selection for DC–DC converters, with experimental testing using hardware and CHIL methods.
Objective 3:
Created MPC fault ride-through control strategies, with stability analyses for dc-dc and ac-dc converters validated by HIL simulations and prototypes. Proposed symmetric and asymmetric multiport Y-converters for AC/DC linkage, incorporating nonlinear and discontinuous modulation to improve integration, mitigate distortion, and enhance performance under renewable profiles—all confirmed through extensive experimental work.
Objective 4:
Devised approaches for optimal MPC sizing and placement, using machine learning for representative day selection. Assessed local and global sizing, applied to buildings and network case studies, introduced GIS-based resilience metrics, and developed investment guidance for fault recovery supported by MPCs.
Objective 5:
Modeled real distribution grids, analyzing flows and SOP converters under varied controls and faults. Optimized MPC operation, performed sensitivity and impact analyses, and validated control techniques using control and power hardware-in-the-loop experiments.
Objective 6:
Conducted techno-economic and life cycle analyses—including carbon footprint assessment—comparing MPCs and single converters. Quantified KPIs for carbon, energy, and materials, and outlined business models for various MPC applications.
Reviewed grid codes and standards for multiport power converters (MPCs) at low and medium voltages, identifying where MPCs deliver value in distribution networks using quantitative KPI metrics. Assessed the strengths and weaknesses of existing MPC topologies, aligned with relevant KPIs. Facilitated partner discussions on the design of low and medium voltage MPCs, using insights from code and topology reviews to define essential port requirements. Developed case studies and compiled data while also reviewing control and communication technologies applicable to MPCs.
Objective 2:
Developed simulation models for isolated, non-isolated, and hybrid multiport converters with two AC ports and one DC port. Designed and experimentally validated modulation and control strategies for various operation scenarios. Explored active bridge DC–DC converters for isolation stages and compared outer-loop control strategies in modular multilevel converters. Implemented grid-forming controls for improved resilience in weak and islanded networks, and compared topologies for soft open point applications. Developed and validated zero-voltage switching optimization and voltage selection for DC–DC converters, with experimental testing using hardware and CHIL methods.
Objective 3:
Created MPC fault ride-through control strategies, with stability analyses for dc-dc and ac-dc converters validated by HIL simulations and prototypes. Proposed symmetric and asymmetric multiport Y-converters for AC/DC linkage, incorporating nonlinear and discontinuous modulation to improve integration, mitigate distortion, and enhance performance under renewable profiles—all confirmed through extensive experimental work.
Objective 4:
Devised approaches for optimal MPC sizing and placement, using machine learning for representative day selection. Assessed local and global sizing, applied to buildings and network case studies, introduced GIS-based resilience metrics, and developed investment guidance for fault recovery supported by MPCs.
Objective 5:
Modeled real distribution grids, analyzing flows and SOP converters under varied controls and faults. Optimized MPC operation, performed sensitivity and impact analyses, and validated control techniques using control and power hardware-in-the-loop experiments.
Objective 6:
Conducted techno-economic and life cycle analyses—including carbon footprint assessment—comparing MPCs and single converters. Quantified KPIs for carbon, energy, and materials, and outlined business models for various MPC applications.
WP1 identified key grid codes and procedures needing development for safe integration of multiport devices into networks. It defined isolation requirements for various MPC ports using DC installation safety zones and created a Pugh Matrix tool for comparing MPC topologies by application. The work established criteria for both isolated and partially isolated MPC suitability, and pinpointed prospects for more capable, non-isolated DC MPCs.
WP2 developed modulation and control strategies for fully isolated MPCs, ensuring dynamic performance under normal and fault conditions. It implemented control of multi-active bridge DC-DC converters, maintaining energy exchange and DC voltage even during active bridge loss. New modulation strategies improved harmonic content and reduced switching losses, with uni-polar and mixed approaches. Non-isolated MPC validation featured classical and crossed energy-based controls for stability under AC and DC faults. Simulations and experiments optimized TAB DC-DC efficiency and reduced current stress. The operational performance of three-port converters was validated in laboratory and CHIL tests.
WP3 introduced fault-ride-through for MPCs and novel stability analysis via MIMO admittance passivity. New topologies offered compact, efficient AC/DC interfacing, verified with experiments and simulations. Nonlinear and discontinuous control for Y-Converters enhanced grid integration and distortion mitigation. Rapid prototyping supported versatile testing.
WP4 developed novel small-signal and stability models for three-port SOPs. New virtual oscillator controllers for MPCs were analyzed for sensitivity. Stability was evaluated under varied conditions, and system-wide coordination techniques were implemented for grid support. CHIL and PHIL tests validated advanced SOP control strategies.
WP2 developed modulation and control strategies for fully isolated MPCs, ensuring dynamic performance under normal and fault conditions. It implemented control of multi-active bridge DC-DC converters, maintaining energy exchange and DC voltage even during active bridge loss. New modulation strategies improved harmonic content and reduced switching losses, with uni-polar and mixed approaches. Non-isolated MPC validation featured classical and crossed energy-based controls for stability under AC and DC faults. Simulations and experiments optimized TAB DC-DC efficiency and reduced current stress. The operational performance of three-port converters was validated in laboratory and CHIL tests.
WP3 introduced fault-ride-through for MPCs and novel stability analysis via MIMO admittance passivity. New topologies offered compact, efficient AC/DC interfacing, verified with experiments and simulations. Nonlinear and discontinuous control for Y-Converters enhanced grid integration and distortion mitigation. Rapid prototyping supported versatile testing.
WP4 developed novel small-signal and stability models for three-port SOPs. New virtual oscillator controllers for MPCs were analyzed for sensitivity. Stability was evaluated under varied conditions, and system-wide coordination techniques were implemented for grid support. CHIL and PHIL tests validated advanced SOP control strategies.